Process for the production of furfural using a water immiscible organic solvent

ABSTRACT

The disclosure relates to an efficient process for the production of a furan derivative from C5 and/or C6 sugars. The process utilizes a water immiscible organic solvent system comprising at least one alkyl phenol and at least one alkylated naphthalene.

FIELD OF THE DISCLOSURE

The present disclosure is directed towards the production of furanderivatives, especially, furfural, 5-hydroxymethylfurfural, and furfurylalcohol from C5 and C6 sugars.

BACKGROUND OF THE DISCLOSURE

Furfural and related compounds, such as 5-hydroxymethyl furfural (HMF),are useful precursors and starting materials for industrial chemicalsfor use as pharmaceuticals, herbicides, stabilizers, fuels, fueladditives and polymers. The current furfural manufacturing processutilizes various biomass, for example, corn cobs, sugar cane bagasse,bamboo, saw dust, wood chippings and oat hulls as a raw material feedstock.

The biomass is hydrolyzed under acidic conditions to its monomer C5and/or C6 sugars, such as glucose, fructose, xylose, mannose, galactose,rhamnose, and arabinose. Xylose, which is a pentose (a C5 sugar) is thesugar present in the largest amount. In an aqueous acidic environment,the C5 sugars are subsequently dehydrated to furfural.

A major difficulty with known methods for dehydration of sugars is theformation of undesirable resinous material called humins that not onlyleads to yield loss but can also lead to the fouling of exposed reactorsurfaces and negatively impact heat transfer characteristics. Thepresent disclosure seeks to minimize the fouling of exposed reactorsurfaces, and also provide a relatively energy efficient method forremoving the products produced from the hydrolysis of the sugarfeedstocks.

SUMMARY OF THE DISCLOSURE

Disclosed is a process comprising:

-   -   A) contacting an aqueous feedstock comprising one or more C5        and/or C6 sugars with an acid catalyst in the presence of a        water immiscible organic solvent at a temperature in the range        of from 90° C. to 250° C. to form a furan derivative and a        residual aqueous feedstock;    -   B) separating the residual aqueous feedstock from the water        immiscible organic solvent;    -   C) optionally, isolating the furan derivative from the water        immiscible organic solvent and    -   D) optionally, removing the residual water or impurities from        the water immiscible organic solvent;        wherein the water immiscible organic solvent comprises a mixture        of at least one alkyl phenol and at least one alkylated        naphthalene.

The disclosure also relates to a composition comprising furfural or5-hydroxymethyl furfural, at least one alkyl phenol, at least onealkylated naphthalene and in the range of from 0 to 5% by weight ofhumins.

DETAILED DESCRIPTION OF THE DISCLOSURE

The features and advantages of the present disclosure will be morereadily understood, by those of ordinary skill in the art from readingthe following detailed description. It is to be appreciated that certainfeatures of the disclosure, which are, for clarity, described above andbelow in the context of separate embodiments, may also be provided incombination in a single element. Conversely, various features of thedisclosure that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any sub-combination.In addition, references to the singular may also include the plural (forexample, “a” and “an” may refer to one or more) unless the contextspecifically states otherwise.

The use of numerical values in the various ranges specified in thisapplication, unless expressly indicated otherwise, are stated asapproximations as though the minimum and maximum values within thestated ranges were both proceeded by the word “about”. In this manner,slight variations above and below the stated ranges can be used toachieve substantially the same results as values within the ranges.Also, the disclosure of these ranges is intended as a continuous rangeincluding each and every value between the minimum and maximum values.

As used herein:

As used herein, the term “sugar” includes monosaccharides,disaccharides, and oligosaccharides. Monosaccharides, or “simplesugars,” are aldehyde or ketone derivatives of straight-chainpolyhydroxy alcohols containing at least three carbon atoms. A pentoseis a monosaccharide having five carbon atoms; some examples are xylose,arabinose, lyxose and ribose. A hexose is a monosaccharide having sixcarbon atoms; some examples are glucose and fructose. Disaccharidemolecules (e.g., sucrose, lactose, and maltose) consist of twocovalently linked monosaccharide units. As used herein,“oligosaccharide” molecules consist of about 3 to about 20 covalentlylinked monosaccharide units.

The term “Cn sugar” includes monosaccharides having n carbon atoms;disaccharides comprising monosaccharide units having n carbon atoms; andoligosaccharides comprising monosaccharide units having n carbon atoms.Thus, “C5 sugar” includes pentoses, disaccharides comprising pentoseunits, and oligosaccharides comprising pentose units.

The term “furan derivative” means furfural, 5-hydroxymethyl furfural,furfuryl alcohol, ethers and esters of 5-hydroxymethyl furfural or acombination thereof. In other embodiments, the furan derivative isfurfural, 5-hydroxymethyl furfural or a combination thereof.

The term “hemicellulose” refers to a polymer comprising C5 and C6monosaccharide units. Hemicellulose consists of short, highly branchedchains of sugars. In contrast to cellulose, which is a polymerconsisting essentially of beta-1,4-linked glucose, a hemicellulose is apolymer of five different sugars. It contains five-carbon sugars(usually D-xylose and L-arabinose) and six-carbon sugars (D-galactose,D-glucose, and D-mannose, fructose). Hemicellulose can also containuronic acid, sugars in which the terminal carbon's hydroxyl group hasbeen oxidized to a carboxylic acid, such as, D-glucuronic acid,4-O-methyl-D-glucuronic acid, and D-galacturonic acid. The sugars arepartially acetylated. Typically, the acetyl content is 2 to 3% by weightof the total weight of hemicellulose. Xylose is typically the sugarmonomer present in hemicellulose in the largest amount.

The term “solid acid catalyst” refers to any solid material containingBrönsted and/or Lewis acid sites, and which is substantially undissolvedby the reaction medium under ambient conditions.

As used herein, the term “heteropolyacid” denotes an oxygen-containingacid with P, As, Si, or B as a central atom which is connected viaoxygen bridges to W, Mo or V. Some examples are phosphotungstic acid,molybdophosphoric acid.

The term “humins” refers to an amorphous byproduct that can form duringthe disclosed process. The formation of humins is believed to occur whenthe furan derivative contacts a C5 and/or C6 sugar in the aqueous phaseforming an oligomeric/polymeric product. The formation of humins canlead to lower yields of the desired product and potentially foul thesurfaces of the equipment used to produce the furan derivative.

The phrase “water immiscible organic solvent” refers to a compositioncomprising at least one alkylated phenol and at least one alkylnaphthalene. In other embodiments, the water immiscible organic solventconsists essentially of at least one alkylated phenol and at least onealkyl naphthalene. The water immiscible organic solvent forms atwo-phase mixture with water at all temperatures of the process, forexample, 90° C. to 250° C. and the water content of the organic solventat 25° C. is less than 5% by weight, based on the total weight of thewater immiscible organic solvent. In other embodiments, water is solublein the water immiscible organic solvent at less than 4%, or less than3%, or less than 2%, or less than 1%, or less than 0.5%, or less than0.1%, wherein all percentage are weight percentages based on the totalweight of the water immiscible organic solvent.

The disclosed process comprises:

-   -   A) contacting an aqueous feedstock comprising one or more 05        and/or C6 sugars with an acid catalyst in the presence of a        water immiscible organic solvent at a temperature in the range        of from 90° C. to 250° C. to form a furan derivative and a        residual aqueous feedstock;    -   B) separating the residual aqueous feedstock from the water        immiscible organic solvent;    -   C) optionally, isolating the furan derivative from the water        immiscible organic solvent; and    -   D) optionally, removing residual water from the water immiscible        organic solvent;    -   wherein the water immiscible organic solvent comprises a mixture        of at least one alkyl phenol and at least one alkylated        naphthalene.

Step A) or the process comprises contacting an aqueous feedstockcomprising one or more C5 and/or C6 sugars with an acid catalyst in thepresence of a water immiscible organic solvent at a temperature in therange of from 90° C. to 250° C. to form a furan derivative and aresidual aqueous feedstock. The water immiscible organic solventcomprises at least one alkyl phenol and at least one alkylatednaphthalene and forms a two phase mixture wherein the aqueous feedstockis one phase and the organic solvent mixture is the other phase.

The source of the aqueous feedstock comprising one or more of C5 and/orC6 sugars can be from any lignocellulosic feedstock or biomass.

The lignocellulosic feedstock or biomass may be derived from a singlesource, or can comprise a mixture derived from more than one source; forexample, biomass can comprise a mixture of corn cobs and corn stover, ora mixture of grass, leaves, bioenergy crops, agricultural residues,municipal solid waste, industrial solid waste, sludge from papermanufacture, yard waste, wood and forestry waste or a combinationthereof. Specific examples of biomass include, but are not limited to,bamboo, palm, corn grain, corn cobs, crop residues such as corn husks,corn stover, corn fiber, grasses, wheat, wheat straw, barley, barleystraw, hay, rice straw, switchgrass, waste paper, sugar cane bagasse,sorghum, soy, components obtained from milling of grains, trees,branches, roots, leaves, wood, wood chips, sawdust, shrubs and bushes,vegetables, fruits, flowers, and animal manure or a combination thereof.Biomass that is useful may include biomass that has a relatively highcarbohydrate value, is relatively dense, and/or is relatively easy tocollect, transport, store and/or handle. In some embodiments, biomassthat is useful includes corn cobs, wheat straw, bamboo, palm, wood,sawdust, sugar cane bagasse or a combination thereof.

Typically, lignocellulosic feedstock or biomass is contacted with waterin the presence of an acid to hydrolyze the material to the C5 and/or C6sugars. In one embodiment, an amount of water is used which is at leastequivalent to that of the lignocellulosic feedstock on a weight basis.Typically, the use of more water provides a more dilute solution of thesugars. However, minimizing the amount of water used generally improvesprocess economics by reducing process volumes. In practical terms, theamount of water used relative to the lignocellulosic feedstock willdepend on the moisture content of the feedstock, as well as the abilityto provide sufficient mixing, or intimate contact, for the biomasshydrolysis to occur at a practical rate. The aqueous feedstock can havein the range of from 0.5% by weight to about 50% by weight of the C5and/or C6 sugars, based on the total weight of the aqueous feedstock. Inother embodiments, the aqueous feedstock can comprise in the range offrom 1% to 40% by weight or in the range of from 1% to about 30% byweight of the C5 and/or 06 sugars. All percentages by weight are basedon the total weight of the aqueous feedstock. In some embodiments, theaqueous feedstock can comprise C5 sugars, and, in other embodiments, theaqueous feedstock can comprise C6 sugars.

The aqueous feedstock is contacted with an acid catalyst. The acidcatalyst is a mineral acid, a heteropolyacid, an organic acid, a solidacid catalyst, carbon dioxide in water, or a combination thereof. Insome embodiments, the acid catalyst is a mineral acid, for example,sulfuric acid, phosphoric acid, hydrochloric acid, or a combinationthereof. In other embodiments, the acid catalyst is a heteropolyacidcomprising phosphotungstic acid, molybdophosphoric acid, or acombination of these. In some embodiments, the acid catalyst is anorganic acid comprising oxalic acid, formic acid, acetic acid, an alkylsulfonic acid, an aryl sulfonic acid, a halogenated acetic acid, ahalogenated alkylsulfonic acid, a halogenated aryl sulfonic acid, or acombination of these. An example of a suitable alkyl sulfonic acid ismethane sulfonic acid. An example of a suitable aryl sulfonic acid istoluenesulfonic acid. An example of a suitable halogenated acetic acidis trifluoroacetic acid, An example of a suitable halogenatedalkylsulfonic acid is trifluoromethane sulfonic acid. An example of asuitable halogenated aryl sulfonic acid is fluorobenzenesulfonic acid.

The solid acid catalyst is a solid acid having the thermal stabilityrequired to survive reaction conditions. The solid acid catalyst may besupported on at least one catalyst support. Examples of suitable solidacids include without limitation the following categories: 1)heterogeneous heteropolyacids (HPAs) and their salts, 2) natural orsynthetic clay minerals, such as those containing alumina and/or silica(including zeolites), 3) cation exchange resins, 4) metal oxides, 5)mixed metal oxides, 6) metal salts such as metal sulfides, metalsulfates, metal sulfonates, metal nitrates, metal phosphates, metalphosphonates, metal molybdates, metal tungstates, metal borates, and 7)combinations of any members of any of these categories. The metalcomponents of categories 4 to 6 may be selected from elements fromGroups 1 through 12 of the Periodic Table of the Elements, as well asaluminum, chromium, tin, titanium, and zirconium. Examples include,without limitation, sulfated zirconia and sulfated titania. Any of theabove listed solid acid catalysts are well known in the art and can beused. Some commercially available examples of solid acid catalysts caninclude, for example, AMBERLYST™ and DOWEX® available from Dow Chemicals(Midland, Mich.) (for example, DOWEX® Monosphere M-31, AMBERLYST™ 15,AMBERLITE™ 120); CG resins available from Resintech. Inc. (West Berlin,N.J.); resins such as MONOPLUS™ S 100H available from Sybron ChemicalsInc. (Birmingham, N.J.), NAFION® perfluorinated sulfonic acid polymer,NAFION® Super Acid Catalyst (a bead-form strongly acidic resin which isa copolymer of tetrafluoroethylene andperfluoro-3,6-dioxa-4-methyl-7-octane sulfonyl fluoride, converted toeither the proton (H⁺), or the metal salt form) available from DuPontCompany (Wilmington, Del.).

The process further includes a water immiscible organic solvent, whereinthe organic solvent is a mixture of at least one alkyl phenol and atleast one alkylated naphthalene. The alkyl phenol is:

wherein R is a C1 to C16 alkyl group; and n is an integer from 1 to 5.The term “alkyl”, includes straight-chain, branched or cyclic alkyl suchas, for example, methyl, ethyl, n-propyl, i-propyl, or the differentbutyl, pentyl or hexyl isomers, including cycloalkyl. The alkyl groupcan be in the ortho (o-), meta- (m-) or para- (p-) positions. In someembodiments, R is a C1 to C12 alkyl group and n is 1 or 2. In stillfurther embodiments, R is a C1 to C6 alkyl and n is 1 or 2. Somespecific embodiments include, for example, tert-butyl phenol, sec-butylphenol, pentyl phenol, hexyl phenol, nonyl phenol and dodecyl phenol. Insome embodiments, R is sec-butyl or tert-butyl. In still furtherembodiments, n is 1 and R is o-sec-butyl, m-sec-butyl, p-sec-butyl,o-tert-butyl, m-tert-butyl or p-tert-butyl. Mixtures of any of thevarious alkyl phenols can also be used.

The water immiscible organic solvent also comprises at least onealkylated naphthalene. Suitable alkylated naphthalenes can comprise:

wherein R¹ is C1 to C6 alkyl, R2 is C1 to C6 alkyl, x is an integer from1 to 4, and y is an integer from 0 to 4. Suitable examples of analkylated naphthalene can include for example, any of the isomers ofmethyl naphthalene, dimethyl naphthalene, ethyl naphthalene, diethylnaphthalene, methyl ethyl naphthalene, propyl naphthalene, butylnaphthalene, pentyl naphthalene, hexyl naphthalene, methyl propylnaphthalene, methyl butyl naphthalene, methyl pentyl naphthalene, methylhexyl naphthalene or a combination thereof. In other embodiments, thealkylated naphthalene is a mixture comprising various alkylatednaphthalenes having a molecular weight in the range of from 128 to 548atomic mass units. In other embodiments, the alkylated naphthalene canhave a molecular weight in the range of from 128 to 296 or from 128 to212 or from 128 to 156 atomic mass units. In still other embodiments,the alkylated naphthalene can be a mixture comprising two or morealkylated naphthalenes. Suitable alkyl naphthalenes can include, forexample, AROMATIC® 200 fluid, AROMATIC® 150 fluid or AROMATIC® 150 NDfluid, all available from Exxon-Mobil. The alkyl naphthalenes may havesmall percentages of aromatic compounds other than naphthalenes. In someembodiments, the alkyl naphthalene may have up to 10% by weight of analkylated benzene. In other embodiments, the alkylated naphthalene mayhave less than 5% by weight or less than 2% by weight or less than 1% byweight of alkylated benzenes. In some embodiments, the alkylatednaphthalene is free from naphthalene.

It has been found that a combination of both an alkyl phenol and analkylated naphthalene can provide a more efficient solvent than eitheralkyl phenols or alkylated naphthalenes can provide by themselves. Alkylphenols are able to solvate a relatively larger amount of water, whencompared to alkylated naphthalenes, which makes the separation of thefuran derivative and recycle of the solvent problematic. Alkylatednaphthalenes on their own, provide a very low water miscibility but arelatively lower partition coefficient for the furan derivative,especially for furfural. Thus, the use of alkyl naphthalenes,exclusively, as the solvent is insufficient due to the low furfuralyields obtained and the insolubility of humins in pure alkylatednaphthalenes, which can result in reactor fouling.

The weight ratio of the at least one alkyl phenol to the at least onealkylated naphthalene can vary in the range of from 100:1 to 1:100,wherein the weight ratio is based on the total weight of the alkylphenol and the alkylated naphthalene. It should be noted that atrelatively higher concentrations of the at least one alkylated phenol,when compared to the at least one alkylated naphthalene, and at hightemperatures, for example, over 100° C. or 125° C. or 150° C. or 175° C.or 200° C., the at least one alkyl phenol may solvate greater than 5% byweight water. For example, it has been found that at around 200° C.using 100% tert-butyl phenol and a solvent to water ratio of 4:1, that asingle phase system can be generated, which is not preferred. Therefore,care should be taken to use relatively lower temperatures, higherconcentrations of the at least one alkylated naphthalene or both inorder to maintain two liquid phases in the reactor. In otherembodiments, the weight ratio of the at least one alkyl phenol to thealkylated naphthalene can be between and optionally include any of thefollowing values: 95:5, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70,20:80, 10:90 and 5:95. In other embodiments, the weight ratio of thealkyl phenol to alkylate naphthalene can be in the range of from 99:1 to1:99 or from 10:90 to 90:10 or from 80:20 to 20:80 or from 70:30 to25:75 or from 60:40 to 25:75 or from 50:50 to 25:75. In one embodiment,the water immiscible organic solvent comprises a combination of at leastone alkyl phenol and at least one alkylated naphthalene. The ratios areby weight, based on the total weight of the alkylated phenol and thealkylated naphthalene. In other embodiments, the water immiscibleorganic solvent consists of or consists essentially of at least onealkyl phenol and at least one alkylated naphthalene. As used in thiscontext, the phrase “consists essentially of” means that the waterimmiscible organic solvent contains less than 10% by weight of compoundsthat are not an alkyl phenol or an alkylated naphthalene, for example,the water miscible organic solvent contains less than 10% by weight ofbenzene or less than 10% by weight of at least one alkylated benzene. Inother embodiments, the phrase consisting essentially of means that thewater miscible organic solvent contains less than 5% or less than 3% orless than 2% or less than 1% by weight of compounds that are not thealkyl phenol or the alkylated naphthalene. The percentage by weight isbased on the total weight of the water immiscible organic solvent.

The weight ratio of the aqueous feedstock to the water immiscibleorganic solvent can vary in the range from 95:5 to 5:95. In otherembodiments, the ratio of the aqueous feedstock to the water immiscibleorganic solvent can be between 10:1 to 1:10. In still furtherembodiments, the ratio can be between 5:1 to 1:5 or from 2:1 to 1:2,wherein the ratios are based on the total weight of the aqueousfeedstock to the weight of the water immiscible organic solvent.

The step of contacting the aqueous feedstock with an acid catalyst inthe presence of the water immiscible organic solvent can take place inany reactor that is suitable for biphasic reactions. For example, theprocess can be carried out in a batch mode using a batch reactor or canbe carried out in a continuous manner using any of the known reactors,for example, a Scheibel column, a continuous stirred tank reactor or aplug flow reactor may be utilized. In some embodiments, the contactingstep occurs by mixing the various components in a vessel.

The reactor can be operated at a variety of temperatures, in the rangeof from 90° C. to 250° C. It has been found that if the amount of thealkyl phenol is high when compared to the amount of the alkylatednaphthalene, and the temperature of the reaction is above 250° C., thenthe water immiscible organic solvent can begin to absorb more than 5% byweight of water. In other embodiments, the temperature of the mixture inthe reactor can be in the range of from 120° C. to 225° C. or from 150°C. to 200° C. The step of contacting can take place for a sufficienttime to convert at least a portion of the C5 and/or C6 sugars to thedesired product. In some embodiments, the reaction time can be in therange of from 1 minute to 24 hours. In other embodiments, the reactiontime can be in the range of from 5 minutes to 12 hours or from 10minutes to 8 hours.

During the contacting step, at least a portion of the C5 and/or C6sugars are converted to one or more furan derivatives, wherein the furanderivatives are more soluble in the water immiscible organic solvent andtherefore, as the reaction progresses the concentration of the furanderivative in the organic phase increases and the concentration of theC5 and/or C6 sugar in the aqueous feedstock decreases, thereby forming aresidual aqueous feedstock having a lower concentration of the sugarthan the aqueous feedstock prior to the contacting step. The products ofthe contacting step can include, for example, one or more furanderivatives, for example furfural, 5-hydroxymethyl furfural or acombination thereof. C5 sugars will generally form furfural while C6sugars will generally form 5-hydroxymethyl furfural. The furanderivative products are more soluble in the water immiscible organicsolvent than in the aqueous phase and therefore, the water immiscibleorganic solvent contains a relatively higher percentage of the productsthan does the aqueous phase, which can minimize the formation ofby-products, for example, humins.

In some embodiments salts can be added to the aqueous feedstock eitherbefore, during or after the contacting step A). The addition of saltscan help to drive the furan derivatives out of the residual aqueousfeedstock and into the water immiscible organic solvent. Suitable saltscan include for example, sodium chloride, calcium chloride, sodiumsulfate, magnesium sulfate, sodium bromide, sodium iodide, potassiumchloride, potassium bromide, potassium iodide, or a combination thereof.The salts can be used in an amount in the range of from 0% to 10% basedon the total weight of the aqueous feedstock. In other embodiments, theamount of salt can be in the range of from 1% to 9% or 2% to 8%. Allpercentages are based on the total weight of the aqueous feedstock.

The step of B) separating the residual aqueous feedstock from the waterimmiscible organic solvent can occur in any suitable vessel. Forexample, the reactor vessel can be used as the separation vessel bystopping the mixing and allowing the two phases to separate. In otherembodiments, a decanter can be used to separate the residual aqueousfeedstock and the water miscible organic solvent comprising the product.The contact of C5 and/or C6 sugars with the acid catalyst produces boththe desired furan derivative and can also produce a byproduct calledhumins. The separation of the humins from both the residual aqueousfeedstock and the water immiscible organic solvent comprising the furanderivative can be accomplished during the separation stage. For example,the humins can be removed by centrifugation, or by using a tricanter. Inanother embodiment, the humins can be removed before or after theseparation of the two liquid phases by filtration.

The step of C) isolating the furan derivative from the water immiscibleorganic solvent can be accomplished by any means known in the art. Insome embodiments, the step of isolating the furan derivative from thewater immiscible organic solvent is a distillation step. It has beenfound that the isolation step using a mixture of the alkyl phenol andthe alkylated naphthalene requires significantly less energy input tovaporize (i.e., distill) the furan derivative and residual water whencompared to using a solvent consisting of alkyl phenol. This results ina much more efficient process. It is believed that since humins are lesssoluble in the water immiscible organic solvent, when compared toalkylated phenol, that they are easier to remove as well. In otherembodiments, the furan derivative can be separated from the waterimmiscible organic solvent by precipitation, adsorption, orchromatography.

The process further comprises an, optional step D) removing residualwater or impurities from the water immiscible organic solvent. In orderto increase the overall efficiency of the process, the water immisciblesolvent can be purified to reuse in step A). The removal step D) can beaccomplished by removing any water by distillation or removingimpurities, for example, humins, by precipitation. It has been foundthat the disclosed water immiscible solvent tends to absorb less waterwhen compared to a solvent system consisting of alkylated phenol.Therefore, in some embodiments, step D) may be a step of removingimpurities from the water immiscible organic solvent. The waterimmiscible organic solvent may be recycled back to step A) with orwithout removal of the water or impurities. Humins that may have formedcan be removed by filtration or centrifugation, as is known in the art.In still further embodiments, the water immiscible organic solvent canbe distilled to provide humin-free water immiscible organic solvent.

The water immiscible organic solvent can then be discarded from theprocess or can be recycled using any methods known in the art for reusein step A). In some embodiments, the water immiscible organic solventcan be added directly back into the process at step A) or can be furtherpurified by removing any humins that may have accumulated in the waterimmiscible organic solvent. In other embodiments, at least a portion ofthe accumulated humins can be removed from the water immiscible organicsolvent and then the at least partially purified water immiscibleorganic solvent can be returned to the process. In this way, thebuild-up of humins in the system can be minimized. Similarly, theresidual aqueous feedstock can be discarded or can be recycled back intothe process with or without any additional purification steps.

In other embodiments, the disclosure comprises a composition comprisingfurfural or 5-hydroxymethyl furfural, at least one alkyl phenol, atleast one alkylated naphthalene and in the range of from 0 to 5% byweight of humins. In still further embodiments, the disclosure relatesto compositions consisting of or consisting essentially of furfural or5-hydroxymethyl furfural, at least one alkyl phenol, at least onealkylated naphthalene and in the range of from 0 to 5% by weight ofhumins

Non-limiting examples of the process disclosed herein include:

-   -   1. A process comprising:    -   A) contacting an aqueous feedstock comprising one or more C5        and/or C6 sugars with an acid catalyst in the presence of a        water immiscible organic solvent at a temperature in the range        of from 90° C. to 250° C. to form a furan derivative and a        residual aqueous feedstock;    -   B) separating the residual aqueous feedstock from the water        immiscible organic solvent;    -   C) optionally, isolating the furan derivative from the water        immiscible organic solvent; and    -   D) optionally, removing residual water or impurities from the        water immiscible organic solvent;    -   wherein the water immiscible organic solvent comprises a mixture        of at least one alkyl phenol and at least one alkylated        naphthalene.    -   2. The process of embodiment 1 wherein the acid catalyst is a        mineral acid, a heteropolyacid, an organic acid, a solid acid        catalyst, carbon dioxide in water or a combination thereof.    -   3 The process of any one of embodiments 1 or 2 wherein the alkyl        phenol is:

wherein R is a C1 to C16 alkyl group; andn is an integer from 1 to 5,

-   -   4. The process of any one of embodiments 1, 2 or 3 wherein the        at least one alkylated naphthalene is:

wherein R¹ is C1 to C6 alkyl;R² is C1 to C6 alkyl;x is an integer from 1 to 4; andy is an integer from 0 to 4.

-   -   5. The process of any one of embodiments 1, 2, 3 or 4 wherein        the water immiscible solvent consists essentially of at least        one alkyl phenol and at least one alkylated naphthalene.    -   6. The process of any one of embodiments 1, 2, 3, 4 or 5 wherein        the furan derivative is furfural, 5-hydroxymethyl furfural or a        combination thereof.    -   7. The process of any one of embodiments 1, 2, 3, 4, 5 or 6        wherein the weight ratio of the at least one alkyl phenol to the        at least one alkylated naphthalene is in the range of from 100:1        to 1:100.    -   8. The process of any one of embodiments 1, 2, 3, 4, 5, 6 or 7        wherein the aqueous feedstock comprises C5 sugars.    -   9. The process of any one of embodiments 1, 2, 3, 4, 5, 6, 7 or        8 wherein the step C) isolating the furan derivative from the        water immiscible organic solvent is a distillation step.    -   10. A composition comprising furfural or 5-hydroxymethyl        furfural, at least one alkyl phenol, at least one alkylated        naphthalene and in the range of from 0 to 5% by weight of        humins.    -   11. The composition of embodiments 10 wherein the composition        consists essentially of furfural or 5-hydroxymethyl furfural, at        least one alkyl phenol, at least one alkylated naphthalene and        in the range of from 0 to 5% by weight of humins.

EXAMPLES

Unless otherwise specified, all the reagents are available from theSigma-Aldrich Chemical Co (St. Louis, Mo.) and/or Alfa Aesar (Ward Hill,Mass.).

In the examples, the following abbreviations are used:

MN—1-methyl naphthalene

2TBP—2-tert-butyl phenol

2SBP—2-sec-butyl phenol

NP—p-nonyl phenol

Example A

Determination of the stability of the water immiscible solvent atreaction temperatures.

Three organic solutions were prepared by combining 1-methylnaphthalene(MN) with the desired alkyl phenol. 1 weight percent oftert-butylbenzene and sulfolane were added as dual internal standards tothe organic solutions (only tert-butylbenzene was needed forquantitative analysis), making these solutions 74 weight percent1-methylnaphthalene, 24 weight percent of the alkyl phenol and 2 weightpercent internal standard. The desired alkyl phenols were2-tertbutylphenol (2TBP), 2-sec-butylphenol (2SBP) and p-nonylphenol(NP). 1 milliliter of each solution was added to 8 different metal tubereactors. To each tube reactor was added 10 microliters (1 volumepercent) of an aqueous acidic solution containing between 25 and 80weight percent, sulfuric acid.

The metal tubes were sealed and were then put into a hot oil bath(initially set at 170° C., this cooled to about 150° C. upon loading itwith the 24 metal tubes) sitting atop a rotary shaker at 100 rpm. Thelid to the heater/shaker was sealed and time 0 was established when theoil heated up to 158° C. The reaction temperature set point was adjustedto and maintained at 160° C. After 45 minutes, the tubes were removedfrom the hot oil and were quenched on ice. The oil was washed off withacetone and the samples were opened. The contents were transferred to 4milliliter vials. 50 microliters of each reaction mixture was added to200 microliters of tetrahydrofuran (THF) in 2 milliliter gaschromatography vials.

Each sample was analyzed using gas chromatography (GC) under thefollowing conditions: Agilent DB-FFAP column (30 meter long×250 microninner diameter and 0.25 micron film thickness), inlet temperature 225°C., helium pressure 1.15 kg/cm², column flow 1.5 milliliters/minute,total flow 211 milliliters/minute, split flow 204 milliliters/minute,split ratio 50:1, 1 microliter injection, detector temperature 250° C.,hydrogen 35 milliliters/minute, air 350 milliliters/minute, makeuphelium 35 milliliters/minute, initial oven temperature 50° C., ramp to80° C. at 10 Celsius/minute, ramp to 200° C. at 20° C./minute, ramp to250° C. at 10° C./minute and hold for 3 minutes.

The 2TBP and 2SBP peaks were calibrated against the two internalstandards. The NP solution was an isomer of various alkyl phenols, sothe sum of the areas of the various peaks was taken to represent anestimate of the total amount of p-nonylphenol. An estimated responsefactor was adjusted such that it gave the proper amount of NP usingthese 8 peaks in the non-heated control reaction mixture. This value wasthen used for the other heated samples.

The ratio of the remaining solvent detected after heating relative tothe initial solvent before heating amount was expressed as a percentageof initial solvent for each of the acid loadings. This was used as ameasure of solvent stability under the acidic conditions. The resultsare shown in TABLE 1.

TABLE 1 Weight Percent of percent initial alkyl sulfuric phenol (tert-acid in 2TBP 2SBP *NP butylbenzene Example aqueous (milli- (milli-(milli- internal No. solution moles) moles) moles) standard) 1 26.6%54.410 n/a n/a 97% 2 32.3% 55.572 n/a n/a 99% 3 44.8% 53.487 n/a n/a 96%4 56.1% 53.100 n/a n/a 95% 5 62.0% 45.693 n/a n/a 82% 6 68.1% 35.861 n/an/a 64% 7 74.0% 31.673 n/a n/a 57% 8 80.1% 25.554 n/a n/a 46% 9 26.6%n/a 54.939 n/a 98% 10 32.3% n/a 53.916 n/a 96% 11 44.8% n/a 53.935 n/a96% 12 56.1% n/a 54.347 n/a 97% 13 62.0% n/a 55.502 n/a 99% 14 68.1% n/a55.250 n/a 99% 15 74.0% n/a 52.214 n/a 93% 16 80.1% n/a 50.761 n/a 91%17 26.6% n/a n/a 37.903 99% 18 32.3% n/a n/a 38.273 100%  19 44.8% n/an/a 39.386 103%  20 56.1% n/a n/a 40.464 106%  21 62.0% n/a n/a 37.94899% 22 68.1% n/a n/a 37.382 98% 23 74.0% n/a n/a 35.791 94% 24 80.1% n/an/a 35.288 92%

The results show that at higher acid levels, t-butyl phenol is lessstable than s-butyl phenol and p-nonylphenol.

Example B

Water Uptake in a Water Immiscible Organic Solvent

An excess of water (greater than 20 wt %) was added to the organicsolvents and the mixtures were vigorously agitated for several minutes.The samples were allowed to sit overnight before being separated bycentrifugation at 4000 rpm for 5 min. The water content of the organicsolvent samples was then measured by adding a known mass of the solventsample to a Mettler Toledo DL31 Karl Fischer Titrator. The titrator usedAQUA STAR® CombiTitrant 5 titrant and HYDRANAL® Methanol Dry solvent.Samples were run in sets of four, and the average value of the four runsis reported in TABLE 2.

TABLE 2 Water in Aromatic organic Phenol hydrocarbon Aromatic solventExample (wt %) Phenol (wt %) hydrocarbon (wt %) 25 5 2TBP 95 MN 0.1 2610 2TBP 90 MN 0.2 27 25 2TBP 75 MN 0.4 28 50 2TBP 50 MN 1.0 Compar- 1002TBP 0 4.0 ative A Compar- 100 2TBP 0 4.2 ative B

The results in TABLE 2 show that the water immiscible organic solvent ofthe disclosure absorbs a significantly less amount of water than does2-tert-butyl phenol as a solvent on its own.

The following methods, described below, were used in the formation offuran derivatives via batch reactors and continuous stirred tankreactors. The contents of the reactors were analyzed using theanalytical methods described below.

Process Method A: Continuous Stirred Tank Reaction

The solvent and aqueous phases were pumped into a continuous stirredtank reactor consisting of a pressure vessel with a nominal volume of100 milliliters (mL) and a working volume of approximately 55 mL. Theliquid level in the reactor was maintained by a dip tube extendingdownward from the top of the reactor. Nitrogen was continually added tothe reactor headspace. The aqueous phase contained the sugar and acidcatalyst. The reactor was agitated at 700 revolutions per minute (rpm)with a pitched blade impeller. The reactor residence time was estimatedby dividing the total volumetric flow rate at the reaction temperatureof the liquid materials entering the reactor by the working volume ofthe reactor. The reactor pressure was maintained above the saturationpressure of water at the reaction temperature by a diaphragm-style backpressure regulator. Reaction samples (5-15 mL) were collected by aliquid handling device from Gilson throughout the reaction. The averagefurfural yield and 5-carbon (C5) sugar conversion at steady state arereported.

Process Method B: Batch Reaction

A 1 liter (L) pressure vessel was charged with a desired amount organicsolvent and aqueous phase. The aqueous phase was prepared with thesugar(s) and the acid catalyst of interest. The total mass of thischarge was generally around 700 grams (g). The pressure vessel wassealed and pressured to 4.83 bar (70 psig) with nitrogen. The vesselcontents were agitated by two pitched blade impellers operating at 1000rpm. The vessel was heated to 170° C. and held at this temperature forat least 1 hour. Samples were taken periodically from the vessel andanalyzed.

Process Method C: Injected Batch Reaction

A 1 L pressure vessel was charged with the desired organic solvent andapproximately 102 g of water and 2.4 g sulfuric acid. The aqueous xylose(24 wt %) and arabinose (16 wt %) solution was added to a piston pump.The pressure vessel was sealed and pressured to 4.83 bar (70 psig) withnitrogen. The vessel contents were agitated by two pitched bladeimpellers operating at 1000 rpm. The vessel was heated to 170° C. Whenthe reactor contents reached the reaction temperature, the aqueousxylose and arabinose solution was added to the reactor through a sampleline preheated to at least 100° C. The addition of the aqueous xyloseand arabinose solution occurred in less than four minutes. The reactiontemperature was maintained for at least 30 minutes (min). Samples weretaken periodically from the vessel and analyzed.

Process Method D: Injected Batch Reaction #2

A 1 L pressure vessel was charged with the desired organic solvent. Anaqueous solution of xylose, arabinose, sulfuric acid and succinic acidwas added to a piston pump. The pressure vessel was sealed and pressuredto 4.83 bar (70 psig) with nitrogen. The vessel contents were agitatedby two pitched blade impellers operating at 1000 rpm. The vessel washeated to 170° C. When the reactor contents reached the reactiontemperature, the aqueous solution was added to the reactor through asample line preheated to at least 80° C. The addition of the aqueoussolution occurred in less than four minutes. The reaction temperaturewas maintained for at least 30 min. Samples were taken periodically fromthe vessel and analyzed.

Analytical Methods

Analytical Method E

Solvent Analysis

Biphasic samples of reaction mixtures were separated and filtered. 200microliters of the filtered organic layer and 200 microliters ofinternal standard solution consisting of 2 weight percent dioxane in1-methylnaphthalene were weighed into a GC vial. The sample wasthoroughly mixed and analyzed on the GC for furfural content.

An Agilent 6890 GC was used for the analysis with the followingparameters: Agilent DB-FFAP column (30 meter long×250 micron innerdiameter and 0.25 micron film thickness), inlet temperature 225 Celsius,helium pressure 16.4 pounds per square inch, column flow 1.5milliliters/minute, total flow 211 milliliters/minute, split flow 204milliliters/minute, split ratio 50:1, 1 microliter injection, detectortemperature 250° C., hydrogen 35 milliliters/minute, air 350milliliters/minute, makeup helium 35 milliliters/minute, initial oventemperature 60° C., ramp to 140° C. at 10° C./minute, ramp to 250° C. at25° C./minute and hold for 3 minutes. The total run time was about 15.4min. Resulting chromatograms were integrated and the raw areas, incombination with the known amount of internal standard, were used forquantitation.

Aqueous Layer

100 microliters of the filtered aqueous layer was weighed into asyringeless filter device (Whatman, UN203NPUORG) with 0.45 micron PTFEmembrane. To the device was weighed 200 microliters of aqueous internalstandard solution consisting of 1 weight percent dimethylsulfoxide. Thetwo liquids were thoroughly mixed and then approximately 20 mg of CaCO3was added to the device to neutralize the acid aqueous phase. Afterneutralization and evolution of gas was completed, the filter insert wasengaged and the filtered sample was analyzed by High Performance LiquidChromatography (HPLC).

An Agilent 1100 series HPLC equipped with degasser, binary pump,autosampler, column heater and refractive index detector modules wasused to analyze furfural and other compounds related to the productionof furfural. The column used was a Bio-Rad Aminex HPX-87P 300 mm×7.8 mmcolumn (Catalog No. 125-0098). To protect this column, the sample firstpassed through a cation and anion combo deashing guard column (CatalogNo. 125-0118) in a stainless steel column holder (Catalog No. 125-0139)and then through a 30 mm×4.6 mm cartridge guard column (Catalog No.125-0119) held in a stainless steel guard column holder (Catalog No.125-0131). The cartridge guard column and the primary column were heatedto 80° C., but the deashing column remained at room temperature. Therefractive index detector used positive polarity and was heated as closeto the column temperature as possible, which was 55° C. Pure 18.2 MOMillipore Dl water was used as the mobile phase. The water was pumpedthrough the column at 0.6 ml min. A 20 microliter injection of eachanalytical sample was initiated for the 60 min run. Resultingchromatograms were integrated and the raw areas, in combination with theknown amount of internal standard, were used for quantitation.

Controls

For each analysis, aqueous and organic control samples with knownconcentrations of sugars and furfural, respectively, were preparedaccording to the methods described previously.

Quantitation

Quantitation of these compounds using either HPLC or GC was always doneby generating calibration curves for the individual analytes such thatthe y axis corresponded to the area ratio of the analyte divided by thearea of the internal standard and the x axis corresponded to the amountof analyte divided by the amount of internal standard. The curves foreach line were linear and were fit through zero. Quantification of realor control samples was done by dividing the ratio of the analyte peakarea to the internal standard peak area by the slope of the calibrationcurve for a particular analyte and then multiplying by the amount ofinternal standard known to be in solution.

Analytical Method F

For these methods, the internal standards, dodecane (0.25-1 wt %) andsuccinic acid (0.5-1 wt %), were added to the solvent and aqueous phasebefore reaction. Post reaction, the aqueous and solvent layers wereallowed to settle, or settling was induced by centrifugation of thesamples at 4000 rpm for 3 min.

Solvent Analysis

300 microliters of the solvent phase was added to 0.45 micrometer filtertype GC vials. These samples were analyzed using the solvent analysistechnique from Method E or by using an Agilent 5890 GC with thefollowing parameters: A DB-17 (30 m×0.32 mm×0.5 μm) capillary column. Aninlet temperature 25° C., helium pressure 10.0 pounds per square inch(0.703 kg/cm²), column flow 2.1 milliliters/minute, septum purge flow of3.7 milliliters/minute, vent flow of 44 milliliters/min, and a 1microliter sample injection. The flame ionization detector was operatedat 250° C. with 35 milliliters/min of hydrogen flow and 350milliliters/min of air flow.

Aqueous Analysis for Furfural

The aqueous, phase was analyzed for furfural by weighing 250 microlitersof an internal standard solution consisting of 0.25 wt % dioxane in2-propanol and 50 microliter of filtered aqueous reaction sample to afilter type GC vial. This sample was then analyzed using the DB-17 GCmethod described above.

Aqueous Phase Sugar Analysis

38 microliters of pyridine, 200 microliters ofN,O-Bis(trimethylsilyl)trifluoroacetamide, and 2 microliters of filteredaqueous sample were added to a GC vial and sealed. These vials were thenheated to 60° C. for 30 min and analyzed on an Agilent 6890 GC with thefollowing conditions: A Supelco Equity 1701: 30 m×0.25 mm×0.25 μm columnrunning a constant He pressure of 19.9 psig. The split ratio was 15:1.The injector temperature was 260° C. and the injection volume was 2microliters. The column oven temperature was started at 140° C., rampedto 210° C. at 6° C./min, ramped to 250° C. at 20° C./min, and then heldfor 4 min.

Quantitation

The same quantitation methods were used as Method E.

Analytical Method G: Octane Internal Standards

This method is the same as Method F, except for the following: 200microliters of the solvent phase and 200 microliters of an internalstandard solution, consisting of 0.65 wt % octane in aromatic 150 fluidnaphthalene depleted, were massed into a filter type GC vial.

Analytical Method H

Post reaction, the aqueous and solvent layers were allowed to settle orsettling was induced by centrifugation of the samples at 4000 rpm for 3min.

Solvent Phase

The solvent phase analysis was analogous to Method F, excepthydroxymethylfurfural was the analyte of interest.

Aqueous Phase

The aqueous phase was analyzed for sugars, fructose andhydroxymethylfurfural using an Agilent 1200 series HPLC with a Bio-RadAminex HPX-87H 300×7.8 millimeter column. The mobile phase was 5millimolar sulfuric acid in water flowing at 0.6 mL/min. The columntemperature was maintained at 40° C. Samples were prepared by adding 250microliters of sample to 900 microliters 50:50 (volume to volume) mix ofacetonitrile and water containing 1 wt % dimethyl sulfoxide. Arefractive index detector was used to detect the analytes.

Sugar Conversion and Product yields were calculated using the followingmethod:

${Conversion}\mspace{11mu} {(X) = {1 - \frac{C_{{reactant},{out}}}{C_{{reactant},{in}}}}}$

The conversion calculation assumes that all of the sugar analytes are inthe aqueous phase.

${{Yield}\mspace{14mu} (Y)} = \frac{C_{{product},{out}}}{C_{{reactant},{in}}}$

Both aqueous and organic, phases were analyzed for product.

Example C

Process Method A and Analytical Method E (analytical) were used. Theresidence time of the reactor was estimated to be 4.5 minutes. Theaqueous phase was 9.7% by weight xylose and 1.5% by weight arabinose. 2%by weight sulfuric acid was the catalyst, and the water immiscibleorganic solvent was AROMATIC™ 200 aromatic fluid with 2TBP added invarious weight percentages, based on the total amount of waterimmiscible organic solvent listed in TABLE 3.

TABLE 3 Solvent:Aq 2TBP Conversion Yield Example ratio (wt %) (%) (%) 293.3 25 45 40 30 2.0 43 43 38 31 4.5 43 56 49 32 3.3 25 52 42 33 3.3 5046 40 34 2.0 7 35 28 35 3.3 25 43 36 36 4.5 7 50 44 37 5.0 25 54 48 383.3 25 58 48 39 1.5 25 36 27 40 2.8 0 37 31 41 3.3 25 43 38 42 3.3 25 4840

Example D

Process Method A and Analytical Method F were used to study the kineticsof the biphasic process by varying the reaction temperature, acidconcentration and residence time according to TABLE 4. The waterimmiscible organic phase was 25% by weight 2TBP in AROMATIC™ 200aromatic fluid or AROMATIC™ 200 ND aromatic fluid. The water immiscibleorganic solvent was used at 3.25 grams of solvent per gram of aqueousphase. The aqueous phase for each of these examples contained 10% byweight xylose. The acid used was sulfuric acid and the amount in TABLE 4is listed as the percentage by weight based on the aqueous phase.

TABLE 4 Acid Residence Temp concentration time Conversion Yield Example(° C.) (%) (minutes) (%) (%) 43 170 2.0 2.9 43 28 44 170 2.0 5.9 60 3845 170 2.0 10.6 66 42 46 170 2.0 19.0 82 53 47 170 1.0 2.8 31 14 48 1701.0 4.4 46 23 49 170 1.0 7.8 42 20 50 170 1.0 12.0 60 29 51 170 1.0 31.276 47 52 170 3.0 3.2 49 30 53 170 3.0 7.0 63 41 54 170 3.0 7.0 63 42 56170 3.0 15.7 79 53 57 180 1.0 3.0 62 30 58 180 1.0 7.3 69 39 59 180 2.07.8 76 47 60 180 2.0 20.2 86 54 61 150 1.0 6.4 22 12 62 150 1.0 13.1 3315 63 150 1.0 21.3 39 19 64 150 1.0 6.4 23 10

The results in TABLES 3 and 4 show that conversion of sugars to furanderivatives in the presence of the water immiscible organic solventreadily occurs over a wide range of temperatures, acid concentrations,and residence times.

Example E

Process Method A and Analytical Method E were used to study theconversion at higher temperatures. In these examples, the ratio of waterimmiscible organic solvent to aqueous phase is 4:1 (wt/wt), theconcentration of xylose in the aqueous phase is 10% by weight and thesulfuric acid concentration is given as a percentage by weight based onthe amount of the aqueous phase. 2TBP and MN were used as the waterimmiscible organic solvent.

TABLE 5 Residence T time wt % acid Conversion Yield Example (° C.)(minutes) phenol (%) (%) (%) Comp C 220 6.7 0 0.10 60 43 Comp D 220 6.70 0.07 59 41 65 200 8.9 25 0.26 35 24 66 200 8.9 25 0.19 35 23

The results in TABLE 5 show that even at relatively high temperatures,the water immiscible organic solvent provides good yields at lowconversions.

Example F

Process method D and Analytical Methods F and G were used to studyeffects of sulfuric acid, solvent to aqueous phase ratio, and solventcomposition on the conversion and yield. The alkylated naphthalenesolvent used in each case was AROMATIC™ solvent, with the grade listedin TABLE 6. ND means a naphthalene depleted grade, which contains lowlevels of naphthalene.

TABLE 6 Example 67 68 69 70 71 Phenol 2TBP 2TBP 2TBP 2TBP 2SBP amt (g)244.0 138.1 135.2 133.2 133.2 wt % 43 25 25 25 25 Alkylated 200 200 200ND 150 ND 200 ND naphthalene amt (g) 327.1 401.0 400.0 399.8 407.6 wt %57 75 75 75 75 Solvent: 4.5 3.2 3.2 3.2 3.2 Aqueous ratio (g/g) Xylose(g) 27.19 33.44 33.57 33.09 33.53 Arabinose (g) 1.26 0.00 0.00 0.00 0.00Water (g) 95.49 129.20 127.30 127.37 129.06 Sugar (wt % 22 20 20 20 20in water) Sulfuric acid 2.56 3.34 3.39 3.31 3.35 (g) Succinic acid 1.321.47 1.37 1.31 1.32 (g) Conversion 96 91 96 96 95 at maximum yield (%)Maximum 63 64 64 63 65 yield (%) Analytical F F F G F Method

Example G

Process methods C and Analytical Method E were used to study the effectof various alkyl phenols on the conversion and yield.

TABLE 7 Example 72 73 Phenol dodecyl phenol nonyl phenol amt (g) 250.0210.0 wt % 45 37.5 AROMATIC ™ 310.0 350.0 200 amt (g) wt % 55 62.5Solvent: 4.1 4.1 Aqueous ratio (g/g) Xylose (g) 7.80 7.80 Arabinose (g)5.23 5.24 Water (g) 121.59 122.50 Sugar 10 10 (wt % in water) Sulfuric2.41 2.42 acid (g) Conversion 98 98 at maximum yield (%) Maximum 20 64yield (%)

Example H

Process Method D and Analytical Method H were used to show that C6sugars could be used to form hydroxymethylfurfural.

TABLE 8 Example 74 Phenol 2TBP amt (g) 135.2 wt % 25 Alkylatednaphthalene AROMATIC ™ 200 ND Amt (g) 400.1 wt % 75 Solvent: 3.3 Aqueousratio (g/g) Fructose (g) 33.55 Water (g) 127.55 Sugar (wt % in water) 20Sulfuric acid (g) 3.38 Succinic acid (g) 1.36 Conversion at maximumyield (%) 90 Maximum yield (%) 55

Example I

Water Uptake in Organic Solvents and Modeling Data

The results of the water uptake from the Karl Fischer Titrationexperiments, shown in example B, were used to determine the watercontent in the organic solvent entering the distillation column. Asecond-order polynomial equation provided an accurate fit to theexperimental data and allowed for interpolation between data points.

ASPEN Calculations for Heat Duty

Modeling of the energy used for the separation of furfural from theorganic solvent was performed in ASPEN Plus v7.3 using the RadFrac blockto simulate distillation. The liquid-liquid equilibrium was calculatedusing the nonrandom, two-liquid (NRTL) model, and the vapor-liquidequilibrium was modeled using the Peng-Robinson equation of state. TheDesign Institute for Physical Properties (DIPPR) database method wasused to calculate the enthalpy. The mixture densities were calculatedfrom the mole fraction average of the pure component liquid molarvolumes. The modeled operating conditions of the distillation columnwere set to approximate a furfural feed of 1000 kg/hr and an organicsolvent rate of 48077 kg/hr, so that 95% of the furfural was removedoverhead, the reboiler temperature was modeled at 170° C., and thecolumn was always run under vacuum. The phrase “calculated heat duty”means the amount of energy required for the separation of thefurfural/water mixture and includes the energy required to preheat thefeed from 30° C. to the desire preheat temperature and the heat added inthe column reboiler as determined by the Aspen modeling. A second-orderpolynomial equation provided an accurate fit to the model results andallowed for interpolation between output points. The results are shownin Table 9.

TABLE 9 Amount Distillation Conditions Calculated of water Feed ColumnHeat Duty 2TBP 1MN (wt %) Water Preheat Pressure (MJ/kg Ex (wt %) (wt %)by KFT (kg/hr) (° C.) (psia) furfural) 75 5 95 0.1 47.1 140 2.2 14.3 7610 90 0.2 76.9 — — 14.4** 77 25 75 0.4 192 — — 15.2** 78 50 50 1.0 472120 2.7 18.0 79 60 40 1.5* 703 120 2.8 19.8 80 70 30 2.0* 949 120 2.921.7 81 80 20 2.6* 1236 120 3.0 23.9 82 100 0 4.0 1910  80 4.0 29.6*Estimated from a second-order polynomial fit to the Karl Fischertitration data. **Estimated from a second-order polynomial fit to theAspen calculation for heat duty.

The results from Table 9 show significantly lower calculated heat dutyfor water immiscible organic solvents containing both the alkyl phenoland the alkylated naphthalene when compared to a solvent consisting of apure alkyl phenol.

What is claimed is:
 1. A process comprising: A) contacting an aqueousfeedstock comprising one or more C5 and/or C6 sugars with an acidcatalyst in the presence of a water immiscible organic solvent at atemperature in the range of from 90° C. to 250° C. to form a furanderivative and a residual aqueous feedstock; B) separating the residualaqueous feedstock from the water immiscible organic solvent; C)optionally, isolating the furan derivative from the water immiscibleorganic solvent; and D) optionally, removing residual water orimpurities from the water immiscible organic solvent; wherein the waterimmiscible organic solvent comprises a mixture of at least one alkylphenol and at least one alkylated naphthalene.
 2. The process of claim 1wherein the acid catalyst is a mineral acid, a heteropolyacid, anorganic acid, a solid acid catalyst, carbon dioxide in water or acombination thereof.
 3. The process of claim 1 wherein the alkyl phenolis:

wherein R is a C1 to C16 alkyl group; and n is an integer from 1 to 5.4. The process of claim 1 wherein the at least one alkylated naphthaleneis:

wherein R¹ is C1 to C6 alkyl; R² is C1 to C6 alkyl; x is an integer from1 to 4; and y is an integer from 0 to
 4. 5. The process of claim 1wherein the water immiscible organic solvent consists essentially of atleast one alkyl phenol and at least one alkylated naphthalene.
 6. Theprocess of claim 1 wherein the furan derivative is furfural,5-hydroxymethyl furfural or a combination thereof.
 7. The process ofclaim 1 wherein the weight ratio of the at least one alkyl phenol to theat least one alkylated naphthalene is in the range of from 100:1 to1:100.
 8. The process of claim 1 wherein the aqueous feedstock comprisesC5 sugars.
 9. The process of claim 1 wherein the step of C) isolatingthe furan derivative from the water immiscible organic solvent is adistillation step.
 10. A composition comprising furfural or5-hydroxymethyl furfural, at least one alkyl phenol, at least onealkylated naphthalene and in the range of from 0 to 5% by weight ofhumins.
 11. The composition of claim 10 consisting essentially offurfural or 5-hydroxymethyl furfural, at least one alkyl phenol, atleast one alkylated naphthalene and in the range of from 0 to 5% byweight of humins.